The present invention relates to a yarn winding machine for winding a plurality of continuously advancing yarns into yarn packages.
A yarn winding machine is disclosed in EP 0 374 536 and corresponding U.S. Pat. No. 5,029,762, wherein the yarn is reciprocated by means of a rotary blade type traversing apparatus along a guide bar with a guide edge. The rotary blade type traversing apparatus comprises oppositely driven rotary blades which are each mounted on a rotor. During its reciprocating movement, the yarn is alternatingly guided by one rotary blade from one end of the traverse stroke to the opposite end thereof. At the end of the traverse stroke, the guiding blade moves below the guide bar, while the oppositely driven blade receives the yarn and guides same to the opposite end of the traverse stroke. While being traversed by the rotary blade, the yarn slides radially along a pushing edge of the rotary blade, so that a constant angular velocity of the rotary blade results in a constantly changing trajectory speed of the yarn and, thus, in a constantly changing traversing speed. This is corrected by the guide bar, which has a curved guiding edge such that while being traversed, the yarn does not essentially change its radial position on the guiding blade.
The above process involves the problem of having to deflect the yarn considerably from the traversing plane. This transverse deflection of the yarn is realized by a corresponding looping on the guide bar, which leads again to friction differences on the yarn and, thus, to fluctuations in the yarn tension. Long traverse strokes of, for example, 250 mm, necessitate a relatively large transverse movement of the yarn, which results again in an unsteady advance of the yarn.
It is therefore the object of the invention to provide an improved winding machine and a method of the described type, such that it becomes possible to deposit the yarn on the package as gently as possible. A further object of the invention is to provide a yarn winding machine which permits winding of packages with a flexible buildup and a simple control of the mass distribution on the package.